1. Field of the Invention
The present invention relates to a solid-state imaging device, a drive method therefor, and an electronic device equipped with the solid-state imaging device.
2. Description of the Related Art
Solid-state imaging devices are roughly classified into two types of solid-state imaging devices typified by a CCD (Charge Coupled Device) image sensor and a CMOS (Complementary Metal Oxide Semiconductor) image sensor. Those solid-state imaging devices are widely used in digital still cameras, digital video cameras, and so forth. Recently, from the viewpoints of a lower supply voltage and lower power consumption, MOS type image sensors are used more as solid-state imaging devices to be installed in mobile devices, such as camera-equipped cellular phones.
As a CMOS solid-state imaging device which achieves simultaneous storage in the individual pixels, a CMOS solid-state imaging device has been proposed which has a memory element (capacitor) provided for each pixel to ensure global shutter imaging. Since a CCD solid-state imaging device has a vertical transfer register and simultaneously into reads electric charges in all the pixels therein, the global shutter imaging can be implemented.
In the CCD solid-state imaging device having a vertical transfer register to ensure global shutter imaging, light leaks into the vertical transfer register, causing a smear. The CCD solid-state imaging device can detect a smear at an optical black pixel region (so-called optical black (OPB) region) for each column. Accordingly, the CCD solid-state imaging device can correct a smear by performing a process of subtracting a signal (OPB data) obtained from the optical black pixel region on from a signal acquired from a pixel (see, for example, JP-A-2006-210560 (Patent Document 1)).